JP2013124084A - Hybrid vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hybrid vehicle which, when a counter electromotive voltage of a generator is higher than a supply voltage to the inverter during power-operated traveling and the vehicle is in a power-running state, cuts off an inverter by gating to improve energy efficiency.SOLUTION: When a vehicle is in a power-running state during its power-operated traveling and a counter electromotive voltage Vmg1 of a motor MG1 is equal to or higher than a voltage VH of a high-voltage system power line, if determination-making power dloss is less than 0, the determination-making power dloss being the sum of increased power dlossV representing power increased by raising the voltage VH of the high-voltage system power line to a necessary voltage VH2 and decreased power dlossG representing power decreased by cutting off an inverter for the motor MG1 by gating, a target voltage VH* is changed to the necessary voltage VH2 and the inverter for the motor MG1 is cut off by gating (S200 to S250). If the determination-making power dloss is equal to or more than 0, the target voltage VH* is not changed and weak field control over the motor MG1 is executed (S260).

Description

  The present invention relates to a hybrid vehicle, and more specifically, a planetary gear in which three rotating elements are connected to three axes of an engine, a generator, a drive shaft connected to the axle, an output shaft of the engine, and a rotating shaft of the generator. Mechanism, electric motor connected to drive shaft, generator inverter for driving generator, motor inverter for driving motor, battery, battery voltage system and generator connected to battery Connected to the drive voltage system to which the inverter for the motor and the inverter for the motor are connected to adjust the voltage of the drive voltage system to be higher than the voltage of the battery voltage system and exchange power between the battery voltage system and the drive voltage system Boost converter, engine operating point, motor torque command, generator torque command and drive voltage system voltage to drive with battery charge / discharge Control means for controlling the boost converter and the engine and the electric motor and a generator Te, relates to a hybrid vehicle equipped with.

  Conventionally, this type of hybrid vehicle includes an engine, a motor MG1, a planetary gear in which a ring gear, a carrier, and a sun gear are respectively connected to a drive shaft coupled to the axle, an engine crankshaft, and a rotation shaft of the motor MG1. In a hybrid vehicle comprising a motor MG2 connected to a drive shaft via a speed reducer, an inverter driving motor MG1, an inverter driving motor MG2, and a battery connected to the inverters of motors MG1 and MG2. When the vehicle is in a power running state or when the vehicle is in a regenerative state and the regenerative power cannot be charged to the battery, the inverter is controlled so that the required power is output from the motor MG2, and the motor MG1 is weakened. The motor MG1 inverter is controlled to perform field processing, and the motor is In the second state where the back electromotive voltage from MG1 is higher than the supply voltage from the battery and the vehicle is in the regenerative state and the battery can be charged, the inverter of the motor MG2 outputs the regenerative torque from the motor MG2. Have been proposed that control the inverter of the motor MG1 so as to shut off the gate (see, for example, Patent Document 1). In this hybrid vehicle, in the second state, the gate of the inverter of the motor MG1 is shut off while the motor is running, so that the power consumption is reduced without performing the field weakening process of the motor MG1, and the counter electromotive force generated in the motor MG1. Is stored in the battery to improve the energy efficiency of the vehicle as a whole.

JP 2009-280033 A

  In the hybrid vehicle described above, the gate of the inverter of the motor MG1 is not shut off when the vehicle is in a power running state while the motor is running. Therefore, the vehicle by gate shutting off the inverter of the motor MG1 when the vehicle is in a power running state while the motor is running. The energy efficiency cannot be improved. On the other hand, when the vehicle is in a power running state while the motor is running, shutting off the inverter of the motor MG1 does not necessarily improve the energy efficiency of the vehicle, and not cutting off the gate improves the energy efficiency of the vehicle. In some cases.

  The hybrid vehicle of the present invention gates the generator inverter even when the vehicle is in a power running state when the counter electromotive voltage of the generator is higher than the voltage supplied to the generator inverter while the motor is running. The main purpose is to improve the energy efficiency of the vehicle.

  The hybrid vehicle of the present invention employs the following means in order to achieve the main object described above.

The hybrid vehicle of the present invention
An engine, a generator, a drive shaft connected to an axle, a planetary gear mechanism in which three rotating elements are connected to three axes of an output shaft of the engine and a rotating shaft of the generator, and connected to the drive shaft A motor, an inverter for a generator for driving the generator, an inverter for a motor for driving the motor, a battery, a battery voltage system to which the battery is connected, the inverter for the generator, and the Connected to a drive voltage system to which an inverter for an electric motor is connected, adjusts the voltage of the drive voltage system to be higher than the voltage of the battery voltage system, and exchanges power between the battery voltage system and the drive voltage system. A boost converter to perform, an operation point of the engine, a torque command of the motor, and a torque command of the generator so as to travel with charging and discharging of the battery In the hybrid vehicle by setting the voltage of the serial driving voltage system and a control means for controlling said boost converter and the generator and the engine and the electric motor,
The control means includes
When the counter electromotive voltage of the generator is higher than the voltage of the drive voltage system while traveling only with power from the electric motor,
When the vehicle is in a regenerative state and the battery is in a chargeable state, the generator inverter is controlled to gate the generator inverter;
When the vehicle is in a regenerative state but the battery is not in a rechargeable state, the generator inverter is controlled to be subjected to field-weakening processing,
When the vehicle is in a power running state, the increased power as the power consumption increased by boosting the voltage of the drive voltage system to a voltage that can be gated off, and the consumption reduced by gate shutting off the generator inverter The determination power is calculated as the sum of the reduced power as the power, and the boost converter is controlled so that the voltage of the drive voltage system can be cut off when the determination power is less than 0. And the generator inverter is controlled so that the generator inverter is gate-cut, and the generator inverter is subjected to field-weakening processing when the power for determination becomes 0 or more. Control,
Means,
It is characterized by that.

  In this hybrid vehicle of the present invention, when the back electromotive force of the generator is higher than the voltage of the drive voltage system to which the invar for the generator and the inverter for the motor are connected while traveling only with the power from the motor, Control according to the case as follows. (1) When the vehicle is in a regenerative state and the battery is in a chargeable state, the generator inverter is controlled so as to shut off the generator inverter. In this case, the control of the electric motor and the control of the boost converter are continued without being changed. (2) When the vehicle is in a regenerative state but the battery is not in a rechargeable state, the generator inverter is controlled so that the generator is subjected to field-weakening processing. Also in this case, the control of the electric motor and the control of the boost converter are continued without being changed. (3) When the vehicle is in a power running state, it decreases by increasing the power consumption as the power consumption increased by boosting the voltage of the drive voltage system to a voltage that can shut off the gate and by shutting off the generator inverter. The determination power is calculated as the sum of the reduced power as the power consumption, and the control is further performed for each case. (3-1) When the determination power is less than 0, the boost converter is controlled so that the voltage of the drive voltage system can be cut off, and the generator inverter is turned off. To control. In this case, the control of the electric motor is continued without being changed. (3-2) When the electric power for determination becomes 0 or more, the generator inverter is controlled so that the generator is subjected to field-weakening processing. In this case, the control of the electric motor and the control of the boost converter are continued without being changed. In this way, the vehicle is in a power running state when the counter electromotive voltage of the generator is higher than the voltage of the drive voltage system to which the invar for the generator or the inverter for the motor is connected while traveling only with the power from the electric motor. Even when the determination power is less than 0, the boost converter is controlled so that the voltage of the drive voltage system can be gated and the generator inverter is gated. By controlling the machine inverter, it is possible to improve the energy efficiency of the vehicle as compared with the case where such control is not performed. Further, the vehicle is in a power running state when the back electromotive force of the generator is higher than the voltage of the drive voltage system to which the invar for the generator or the inverter for the motor is connected while traveling only with the power from the motor. Sometimes, when the determination power becomes 0 or more, the generator inverter is controlled so that the generator is subjected to field-weakening processing, so that when the determination power becomes 0 or more, the voltage of the drive voltage system is reduced. It is possible to suppress a decrease in the energy efficiency of the vehicle due to controlling the boost converter so as to obtain a voltage that can shut off the gate, and controlling the generator inverter so as to gate the generator inverter. Here, “the vehicle is in a regenerative state” means a state where a braking force is applied to the vehicle as a whole by the electric motor and the generator, and “the vehicle is in a power running state” means that the electric motor and It means a state in which a driving force is applied to the vehicle as a whole by the generator. Further, “increased power” has a positive value when increasing, and “decreasing power” has a negative value when decreasing. Therefore, when “determination power” is a positive value, the power consumption increases as a whole, and when “determination power” is a negative value, the power consumption decreases as a whole.

  “Increased power” tends to increase as the difference voltage obtained by subtracting the voltage set as the drive voltage system voltage from the voltage that can shut off the inverter for the generator increases. It can be obtained using a map set to increase as the flowing current increases, and “reduced power” can be obtained using a map set to increase as the number of revolutions of the generator increases. can do. Such a map can be determined by determining specifications of an engine, a generator, an electric motor, a planetary gear mechanism, a boost converter, an inverter for a generator, an inverter for an electric motor, and the like, and performing an experiment or the like.

1 is a configuration diagram showing an outline of a configuration of a hybrid vehicle 20 as an embodiment of the present invention. It is a block diagram which shows the outline of a structure of an electric drive system. 4 is a flowchart illustrating an example of a motor travel control routine that is executed by the hybrid electronic control unit. It is explanatory drawing which shows an example of the map for request | requirement torque setting. It is explanatory drawing which shows an example of the relationship between the difference voltage (DELTA) V (VH2-VH) obtained by subtracting the voltage VH of the high voltage type | system | group electric power line 54a from the required voltage VH2, the electric current which flows into the boost converter 55, and the increase electric power dlossV. It is explanatory drawing which shows an example of the relationship between the rotation speed Nm1 of motor MG1, and reduction electric power dlossG.

  Next, the form for implementing this invention is demonstrated using an Example.

  FIG. 1 is a configuration diagram showing an outline of the configuration of a hybrid vehicle 20 as an embodiment of the present invention. As shown in the figure, the hybrid vehicle 20 of the embodiment includes an engine 22 configured as an internal combustion engine that outputs power using a hydrocarbon-based fuel such as gasoline or light oil, and an engine electronic control unit that controls the drive of the engine 22. (Hereinafter referred to as the engine ECU) 24 and a drive shaft connected to a crankshaft 26 as an output shaft of the engine 22 with a plurality of pinion gears connected thereto and connected to drive wheels 38a and 38b via a differential gear 37 A planetary gear 30 having a ring gear connected to 32, a motor MG1 configured as a synchronous generator motor and having a rotor connected to the sun gear of the planetary gear 30, and a rotor connected to the drive shaft 32, for example, configured as a synchronous generator motor. Motor MG2 and motor MG1, Inverters 41 and 42 for driving G2, a motor electronic control unit (hereinafter referred to as motor ECU) 40 for driving and controlling motors MG1 and MG2 by switching control of inverters 41 and 42, and a lithium ion secondary battery, for example A configured battery 50, a battery electronic control unit (hereinafter referred to as a battery ECU) 52 for managing the battery 50, a power line (hereinafter referred to as a high voltage system power line) 54a connected to the inverters 41 and 42, and a battery 50 is connected to a power line 54b (hereinafter referred to as a battery voltage system power line) 54b, and the voltage VH of the high voltage system power line 54a is adjusted within a range equal to or higher than the voltage VL of the battery voltage system power line 54b. Between the high voltage system power line 54a and the low voltage system power line 54b Boost converter 55 for exchanging power, smoothing capacitor 57 connected to the positive and negative buses of high voltage power line 54a, and the positive and negative buses of battery voltage power line 54b are connected in a similar manner. The smoothing capacitor 58 and a hybrid electronic control unit 70 for controlling the entire vehicle are provided.

  Each of the motor MG1 and the motor MG2 is configured as a known synchronous generator motor including a rotor in which a permanent magnet is embedded and a stator around which a three-phase coil is wound. As shown in the block diagram of the electric drive system including the motors MG1 and MG2 in FIG. 2, the inverters 41 and 42 are in reverse directions to the six transistors T11 to T16 and T21 to 26 and the transistors T11 to T16 and T21 to T26. 6 diodes D11 to D16, D21 to D26 connected in parallel. Two transistors T11 to T16 and T21 to T26 are arranged in pairs so as to be on the source side and the sink side with respect to the positive and negative buses of the high voltage power line 54a, respectively. The three-phase coils (U-phase, V-phase, W-phase) of the motors MG1, MG2 are connected to the connection points. Therefore, the three-phase coil is controlled by controlling the on-time ratio of the transistors T11 to T16 and T21 to T26 that make a pair in a state where a voltage is applied between the positive and negative buses of the high voltage power line 54a. Thus, a rotating magnetic field can be formed, and the motors MG1 and MG2 can be driven to rotate. Since the inverters 41 and 42 share the positive and negative buses of the high voltage system power line 54a, the electric power generated by one of the motors MG1 and MG2 can be supplied to another motor.

  The motor ECU 40 is configured as a microprocessor centered on a CPU (not shown), and includes a ROM, a RAM, an input / output port, and a communication port in addition to the CPU. The motor ECU 40 receives signals necessary for driving and controlling the motors MG1 and MG2, for example, the rotational positions of the rotors of the motors MG1 and MG2 from the rotational position detection sensors 43 and 44 that detect the rotational positions of the rotors of the motors MG1 and MG2. The rotational position, the phase current applied to the motors MG1 and MG2 detected by a current sensor (not shown), the inverter temperature from a temperature sensor (not shown) attached to the inverters 41 and 42, and the like are input. Switching control signals to the transistors T11 to T16 and T21 to 26 of the inverters 41 and 42 are output. The motor ECU 40 is in communication with the hybrid electronic control unit 70, controls the driving of the motors MG1 and MG2 by a control signal from the hybrid electronic control unit 70, and, if necessary, data on the operating state of the motors MG1 and MG2. Output to the hybrid electronic control unit 70. The motor ECU 40 also calculates the rotational speeds Nm1, Nm2 of the motors MG1, MG2 based on the rotational positions of the rotors of the motors MG1, MG2 from the rotational position detection sensors 43, 44.

  As shown in FIG. 2, the boost converter 55 is configured as a boost converter including two transistors T31 and T32, two diodes D31 and D32 connected in parallel to the transistors T31 and T32 in a reverse direction, and a reactor L. . The two transistors T31 and T32 are respectively connected to the positive bus of the high voltage system power line 54a and the negative bus of the high voltage system power line 54a and the battery voltage system power line 54b, and the reactor L is connected to the connection point. Has been. The positive terminal and the negative terminal of the high-voltage battery 50 are connected to the reactor L and the negative buses of the high voltage system power line 54a and the battery voltage system power line 54b, respectively. Therefore, by turning on / off the transistors T31 and T32, the power of the battery voltage system power line 54b is boosted and supplied to the high voltage system power line 54a, or the power of the high voltage system power line 54a is reduced to reduce the battery voltage. Or can be supplied to the system power line 54b.

  The battery ECU 52 is configured as a microprocessor centered on a CPU (not shown), and includes a ROM, a RAM, an input / output port, and a communication port in addition to the CPU. In the battery ECU 52, signals necessary for managing the battery 50, for example, voltage between terminals from a voltage sensor (not shown) installed between the terminals of the battery 50, battery voltage system power connected to the output terminal of the battery 50 A charge / discharge current from a current sensor (not shown) attached to the line 54b, a battery temperature from a temperature sensor (not shown) attached to the battery 50, and the like are input, and data on the state of the battery 50 is communicated as necessary. Output to the hybrid electronic control unit 70. In addition, the battery ECU 52 manages the battery 50, and the power storage that is the ratio of the stored power amount stored in the battery 50 based on the integrated value of the charge / discharge current detected by the current sensor to the total capacity (power storage capacity). The ratio SOC is calculated, and the input / output limits Win and Wout, which are the maximum allowable power that may charge / discharge the battery 50, are calculated based on the calculated storage ratio SOC and the battery temperature Tb. The input / output limits Win and Wout of the battery 50 are set to the basic values of the input / output limits Win and Wout based on the battery temperature Tb, and the output limiting correction coefficient and the input limiting limit are set based on the storage ratio SOC of the battery 50. It can be set by setting a correction coefficient and multiplying the basic value of the set input / output limits Win and Wout by the correction coefficient.

  The hybrid electronic control unit 70 is configured as a microprocessor centered on the CPU 72, and in addition to the CPU 72, a ROM 74 for storing processing programs, a RAM 76 for temporarily storing data, an input / output port and communication not shown. And a port. In the hybrid electronic control unit 70, the voltage of the capacitor 57 (the voltage of the high voltage system power line 54 a) VH from the voltage sensor 57 a attached between the terminals of the capacitor 57 and the voltage sensor attached between the terminals of the capacitor 58. The voltage of the capacitor 58 from 58a (the voltage of the battery voltage system power line 54b) VL, the ignition signal from the ignition switch 80, the shift position SP from the shift position sensor 82 that detects the operation position of the shift lever, and the depression amount of the accelerator pedal Accelerator opening degree Acc from the accelerator pedal position sensor 84 that detects the amount of depression, brake pedal position BP from the brake pedal position sensor 86 that detects the amount of depression of the brake pedal, vehicle speed V from the vehicle speed sensor 88, storage of the battery 50 EV for instructing electric travel that travels only with the power from motor MG2 in a state where the operation of engine 22 is stopped until the lower limit ratio Smin that is set in advance as the lower limit value of the storage ratio that permits electric travel An EV switch signal EVSW or the like from the switch 89 is input via the input port, and a switching control signal to the transistors T31 and T32 of the boost converter 55 is output from the hybrid electronic control unit 70 via the output port. Has been. As described above, the hybrid electronic control unit 70 is connected to the engine ECU 24, the motor ECU 40, and the battery ECU 52 via the communication port, and exchanges various control signals and data with the engine ECU 24, the motor ECU 40, and the battery ECU 52. ing.

  The hybrid vehicle 20 of the embodiment configured in this way calculates the required torque to be output to the drive shaft 32 based on the accelerator opening Acc and the vehicle speed V corresponding to the amount of depression of the accelerator pedal 83 by the driver. The operation of the engine 22, the motor MG1, and the motor MG2 is controlled so that the required power corresponding to the torque is output to the drive shaft 32. As the operation control of the engine 22, the motor MG1, and the motor MG2, the operation of the engine 22 is controlled so that power corresponding to the required power is output from the engine 22, and all of the power output from the engine 22 is transmitted to the planetary gear 30 and the motor MG1. And the motor MG2 convert the torque and output to the drive shaft 32. The torque conversion operation mode for driving and controlling the motor MG1 and the motor MG2 and the power suitable for the sum of the required power and the power required for charging and discharging the battery 50 are obtained. The operation of the engine 22 is controlled so as to be output from the engine 22, and all or a part of the power output from the engine 22 with charging / discharging of the battery 50 is converted by the planetary gear 30, the motor MG1, and the motor MG2. Accordingly, the required power is output to the drive shaft 32. Charge-discharge drive mode for driving and controlling the motor MG1 and the motor MG2, there is a motor operation mode in which operation control to output a power commensurate to stop the operation of the engine 22 to the required power from the motor MG2 to the drive shaft 32. Both the torque conversion operation mode and the charge / discharge operation mode are modes in which the engine 22 and the motors MG1, MG2 are controlled so that the required power is output to the drive shaft 32 with the operation of the engine 22. Can be considered as an engine operation mode. Here, since the engine operation mode involves the operation of the engine 22 and the driving of the motors MG1 and MG2, it is also referred to as a hybrid mode (HV mode). The motor operation mode is determined from the motor MG2 while the operation of the engine 22 is stopped. Since the vehicle travels only with the power of the motor, it is referred to as an electric travel mode (EV mode).

  In the engine operation mode (HV mode), the hybrid electronic control unit 70 requires the required torque Tr to be output to the drive shaft 32 based on the accelerator opening Acc from the accelerator pedal position sensor 84 and the vehicle speed V from the vehicle speed sensor 88. * Is set, and the required torque Tr * is set and multiplied by the rotation speed Nr of the drive shaft 32 (for example, the rotation speed obtained by multiplying the rotation speed Nm2 of the motor MG2 or the vehicle speed V by a conversion factor). The charge / discharge required power Pb * of the battery 50 obtained based on the power storage ratio SOC of the battery 50 from the calculated travel power Pdrv * is calculated (the positive value when discharging from the battery 50). The required power Pe * is set as the power to be reduced and output from the engine 22, and the required power Pe * is efficiently set. The target rotational speed Ne * and the target torque Te * of the engine 22 are set using an operation line (for example, a fuel efficiency optimal operation line) as a relationship between the rotational speed Ne of the engine 22 and the torque Te that can be output from the engine 22. Then, a torque command Tm1 * as a torque to be output from the motor MG1 is set by rotational speed feedback control for rotating the engine 22 at the target rotational speed Ne * within the range of the input / output limits Win and Wout of the battery 50. At the same time, when the motor MG1 is driven with the torque command Tm1 *, the torque acting on the drive shaft 32 via the planetary gear 30 is subtracted from the required torque Tr * to set the torque command Tm2 * of the motor MG2, and the target rotational speed Ne * The target torque Te * is transmitted to the engine ECU 24, and torque commands Tm1 *, Tm * For information about to send to the motor ECU40. The engine ECU 24 that has received the target rotational speed Ne * and the target torque Te * then controls the intake air amount and the fuel injection control in the engine 22 so that the engine 22 is operated by the target rotational speed Ne * and the target torque Te *. Perform ignition control. The motor ECU 40 that has received the torque commands Tm1 * and Tm2 * performs switching control of the transistors T11 to T16 and T21 to T26 of the inverters 41 and 42 so that the motors MG1 and MG2 are driven by the torque commands Tm1 * and Tm2 *. Do. Further, the hybrid electronic control unit 70 is based on the voltage necessary for driving the motor MG1 based on the rotational speed Nm1 of the motor MG1 and the torque command Tm1 *, the rotational speed Nm2 of the motor MG2, and the torque command Tm2 *. The larger one of the voltages required to drive the motor MG2 is set as the target voltage VH * of the high voltage system power line 54a and boosted so that the voltage VH of the high voltage system power line 54a becomes the target voltage VH *. Switching control of the switching elements Tr31 and Tr32 of the converter 55 is performed. In this engine operation mode (HV mode), the operation of the engine 22 is stopped when the required power Pe * of the engine 22 is equal to or less than a stop threshold value Pstop that is determined as a better value when the engine 22 is stopped. Shift to the motor operation mode (EV mode).

  In the motor operation mode (EV mode), the hybrid electronic control unit 70 sets a required torque Tr * to be output to the drive shaft 32 based on the accelerator opening Acc and the vehicle speed V, and a torque command Tm1 * of the motor MG1. And a torque command Tm2 * of the motor MG2 is set so that the required torque Tr * is output to the drive shaft 32 within the range of the input / output limits Win and Wout of the battery 50, and these are transmitted to the motor ECU 40. To do. The motor ECU 40 that receives the torque commands Tm1 * and Tm2 * performs switching control of the transistors T11 to T16 and T21 to 26 of the inverters 41 and 42 so that the motors MG1 and MG2 are driven by the torque commands Tm1 * and Tm2 *. Do. Further, the hybrid electronic control unit 70 sets the voltage required to drive the motor MG2 as the target voltage VH * of the high voltage system power line 54a based on the rotational speed Nm2 of the motor MG2 and the torque command Tm2 *. The switching elements Tr31 and Tr32 of the boost converter 55 are subjected to switching control so that the voltage VH of the high voltage system power line 54a becomes the target voltage VH *. In this motor operation mode (EV mode), the engine 22 obtained by subtracting the charge / discharge required power Pb * of the battery 50 from the travel power Pdrv * obtained by multiplying the required torque Tr * by the rotational speed Nr of the drive shaft 32. When the required power Pe * reaches or exceeds a starting threshold value Pstart that is determined as a value that is better when the engine 22 is started, the engine 22 is started and the engine operation mode (HV mode) is entered.

  Next, when the back electromotive voltage Vmg1 of the motor MG1 becomes higher than the voltage VH of the high voltage system power line 54a when the hybrid vehicle 20 of the embodiment configured as described above is operated electrically, particularly in the motor operation mode. Will be described. FIG. 3 is a flowchart illustrating an example of a motor travel control routine executed by the hybrid electronic control unit 70. This routine is repeatedly executed every predetermined time (for example, every several msec) during the electric running in the motor operation mode.

  When the motor travel control routine is executed, the CPU 72 of the hybrid electronic control unit 70 first starts from the accelerator opening Acc from the accelerator pedal position sensor 84, the brake pedal position BP from the brake pedal position sensor 86, and the voltage sensor 57a. A process for inputting data necessary for control such as the voltage VH of the high-voltage power line 54a, the vehicle speed V from the vehicle speed sensor 88, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2, and the input and output limits Win and Wout of the battery 50 Execute (Step S100). Here, the rotational speeds Nm1 and Nm2 of the motors MG1 and MG2 are input from the motor ECU 40 by communication from those calculated based on the rotational positions of the rotors of the motors MG1 and MG2 detected by the rotational position detection sensors 43 and 44. To do. The input / output limits Win and Wout of the battery 50 are set from the battery ECU 52 by communication from the battery temperature Tb of the battery 50 detected by the temperature sensor 51c and the remaining capacity (SOC) of the battery 50 by communication. To do. The input / output limits Win and Wout of the battery 50 are set to the basic values of the input / output limits Win and Wout based on the battery temperature Tb, and the output limiting correction coefficient and input based on the remaining capacity (SOC) of the battery 50 It can be set by setting a correction coefficient for restriction and multiplying the basic value of the set input / output restrictions Win and Wout by the correction coefficient.

  When the data is input in this way, the torque required for the vehicle is output to the ring gear shaft 32a as the drive shaft connected to the drive wheels 38a, 38b based on the input accelerator opening Acc, brake pedal position BP, and vehicle speed V. Power demand torque Tr * is set (step S110). In the embodiment, the required torque Tr * is stored in the ROM 74 as a required torque setting map by predetermining the relationship among the accelerator opening Acc, the brake pedal position BP, the vehicle speed V, and the required torque Tr *. When Acc and vehicle speed V are given, the corresponding required torque Tr * is derived and set from the stored map. FIG. 4 shows an example of the required torque setting map.

  Next, by dividing the input / output limits Win and Wout of the battery 50 by the rotation speed Nm2 of the motor MG2, torque limits Tmin and Tmax as upper and lower limits of torque are calculated by the following expressions (1) and (2) ( In step S120, the set required torque Tr * is set as a temporary torque Tm2tmp which is a temporary value of torque to be output from the motor MG2 (step S130), and the temporary motor torque Tm2tmp is limited by the calculated torque limits Tmin and Tmax. The torque command Tm2 * of the motor MG2 is set as a value (step S140). By setting the torque command Tm2 * of the motor MG2 in this way, the required torque Tr * output to the ring gear shaft 32a as the drive shaft is set as a torque limited within the range of the input / output limits Win and Wout of the battery 50. can do.

Tmin = Win / Nm2 (1)
Tmax = Wout / Nm2 (2)

  Next, the target voltage VH * as a target value of the voltage VH of the high voltage system power line 54a is set based on the rotational speed Nm2 of the motor MG2 and the torque command Tm2 * (step S150), and the rotational speed of the motor MG1. Based on Nm1, the counter electromotive voltage Vmg1 of the motor MG1 is set (step S160). Here, the target voltage VH * has a tendency to increase as the rotational speed Nm2 of the motor MG2 increases, and to increase as the torque command Tm2 * increases, and is as low as possible within a range where the motor MG2 can be driven. Set as In the embodiment, the relationship between the rotational speed Nm2 of the motor MG2, the torque command Tm2 *, and the target voltage VH * is determined in advance and stored in the ROM 74 as a target voltage setting map, and the rotational speed Nm2 of the motor MG2 and the torque command Tm2 are stored. When * is given, the corresponding target voltage VH * is derived and set from the map. When the target voltage VH * is set, the switching element of the boost converter 55 is set so that the voltage VH of the high voltage system power line 54a becomes the target voltage VH * by a boost control routine (not shown) executed by the hybrid electronic control unit 70. Tr31 and Tr32 are controlled. Further, the counter electromotive voltage Vmg1 of the motor MG1 can be obtained from the rotational speed Nm1 of the motor MG1. In the embodiment, the relationship between the rotational speed Nm1 of the motor MG1 and the back electromotive voltage Vmg1 is examined and stored in the ROM 74 as a back electromotive voltage setting map, and when the rotational speed Nm1 of the motor MG1 is given, the corresponding reverse from the map. The electromotive voltage Vmg1 was derived and set.

  Subsequently, the set back electromotive voltage Vmg1 of the motor MG1 is compared with the voltage VH of the high voltage system power line 54a (step S170). When the back electromotive voltage Vmg1 of the motor MG1 is less than the voltage VH, an inverter that drives the motor MG1. A gate shutoff command for shutting off the gate 41 and a torque command Tm2 * for the motor MG2 are transmitted to the motor ECU 40 (step S250), and this routine is terminated. The motor ECU 40 that has received the gate cutoff command and the torque command Tm2 * of the inverter 41 controls the switching of the switching element of the inverter 42 so that the gate of the inverter 41 is shut off and the motor MG2 is driven by the torque command Tm2 *. Thus, when the back electromotive voltage Vmg1 of the motor MG1 is less than the voltage VH of the high voltage system power line 54a, the current caused by the back electromotive voltage Vmg1 of the motor MG1 does not flow to the high voltage system power line 54a. By cutting off the gate, power consumption can be suppressed without performing field weakening control on the motor MG1.

  When it is determined in step S170 that the back electromotive voltage Vmg1 of the motor MG1 is equal to or higher than the voltage VH of the high voltage system power line 54a, the vehicle is in a regenerative state in which a braking force is output or the vehicle is running. Is output to check whether the vehicle is running (step S180). Here, whether the vehicle is in a regenerative power running state can be determined based on whether the required torque Tr * is a negative value or a positive value. When the vehicle is in a regenerative state, it is determined whether or not the battery 50 can be charged based on the input limit Win of the battery 50 or the storage rate SOC (step S190), and the battery 50 is in a state where it can be charged. In some cases, a gate shutoff command for gate shutting off the inverter 41 that drives the motor MG1 and a torque command Tm2 * for the motor MG2 are transmitted to the motor ECU 40 (step S250), this routine is finished, and the battery 50 can be charged. If not, the torque command Tm1 * of the motor MG1 and the torque command Tm2 * of the motor MG2 set by setting the torque command Tm1 * of the motor MG1 to 0 are transmitted to the motor ECU 40 (step S260), and this routine is terminated. To do. Receiving the torque commands Tm1 * and Tm2 *, the motor ECU 40 controls the motor MG1 to be driven with a torque of 0, that is, performs switching control of the switching element of the inverter 41 so as to perform field weakening control, and torque command Tm2 *. Thus, switching control of the switching element of the inverter 42 is performed so that the motor MG2 is driven. Thus, when the vehicle is in a regenerative state and the back electromotive voltage Vmg1 of the motor MG1 is equal to or higher than the voltage VH of the high voltage system power line 54a and the input limit Win of the battery 50 is small or the storage ratio SOC is large, charging is not possible. By performing field weakening control on the motor MG1, it is possible to prevent a current caused by the counter electromotive voltage Vmg1 of the motor MG1 from flowing through the high voltage system power line 54a.

  When it is determined in step S180 that the state of the vehicle is a power running state in which driving force is output and traveling, a margin voltage is added to the counter electromotive voltage Vmg1 of the motor MG1 in order to stably shut off the inverters 41 and 42. Is added to set the required voltage VH2 as a voltage that can shut off the inverter 41 of the motor MG1 (step S200), and the voltage VH of the high voltage system power line 54a is boosted to the required voltage VH2 to increase the consumption. The increased power dlossV as the power and the reduced power dlossG as the power consumption that decreases by shutting off the gate of the inverter 41 are set (step S210). Here, as the margin voltage, for example, a value of about 1% to several percent of the allowable maximum voltage of the high voltage system power line 54a can be used, but a value of 0 may be used as the margin voltage. In this case, the required voltage VH2 becomes the counter electromotive voltage Vmg1 of the motor MG1, and when the counter electromotive voltage Vmg1 of the motor MG1 fluctuates, the required voltage VH2 lacks some stability. In the embodiment, the increased power dlossV is a power that takes a positive value when the power consumption increases when the voltage VH of the high voltage system power line 54a is boosted to the required voltage VH2, and the high voltage system is increased from the required voltage VH2. The relationship between the difference voltage ΔV (VH2−VH) obtained by reducing the voltage VH of the power line 54a, the current flowing through the boost converter 55, and the increased power dlossV is obtained in advance and stored in the ROM 74 as an increased power setting map. When the difference voltage ΔV (VH2−VH) and the current flowing through the boost converter 55 are given, the corresponding increased power dlossV is derived from the map and set. FIG. 5 shows an example of the relationship between the differential voltage ΔV (VH2−VH), the current flowing through the boost converter 55, and the increased power dlossV. As shown in the figure, the increased power dlossV is set so as to increase as the differential voltage ΔV (VH2−VH) increases and to increase as the current flowing through the boost converter 55 increases. In the embodiment, the reduced power dlossG is a negative power when the power consumption is reduced by shutting off the inverter 41 of the motor MG1, and the relationship between the rotational speed Nm1 of the motor MG1 and the reduced power dlossG. It is determined in advance and stored in the ROM 74 as a reduced power setting map, and when the rotational speed Nm1 of the motor MG1 is given, the corresponding reduced power dlossG is derived and set from the map. An example of the relationship between the rotational speed Nm1 of the motor MG1 and the reduced power dlossG is shown in FIG. As illustrated, in the embodiment, the reduced power dlossG is set such that the absolute value thereof increases as the rotational speed Nm1 of the motor MG1 increases. The increased power dlossV and the decreased power dlossG vary depending on the specifications of the engine 22, the motors MG1, MG2, the planetary gear 30, the battery 50, the boost converter 55, and the inverters 41, 42. It is necessary to obtain the relationship through experiments.

  When the increased power dlossV and the decreased power dlossG are thus set, the determination power dloss is calculated as the sum of the increased power dlossV and the decreased power dlossG (step S220), and whether or not the calculated determination power dloss is greater than or equal to 0. (Step S230), and when the determination power dloss is greater than or equal to 0, the voltage VH of the high voltage system power line 54a is boosted to the required voltage VH2 to weaken the motor MG1 rather than shutting off the inverter 41. It is determined that the field control is more energy efficient, and the torque command Tm1 * of the motor MG1 and the torque command Tm2 * of the motor MG2 set by setting the torque command Tm1 * of the motor MG1 to 0 is transmitted to the motor ECU 40. (Step S260), this routine is finished. Thus, when the vehicle is in a power running state and the counter electromotive voltage Vmg1 of the motor MG1 is equal to or higher than the voltage VH of the high voltage system power line 54a, the target voltage VH * is changed when the determination power dloss is 0 or more. Instead, by performing field weakening control on the motor MG1, current caused by the counter electromotive voltage Vmg1 of the motor MG1 is prevented from flowing to the high voltage system power line 54a.

  On the other hand, if it is determined in step S230 that the determination power loss is less than 0, it is better to boost the voltage VH of the high voltage system power line 54a to the required voltage VH2 and to gate the inverter 41 to the motor MG1. Therefore, it is determined that the energy efficiency is higher than the field-weakening control, and the target voltage VH * is changed with the required voltage VH2 as the new target voltage VH * (step S240), and the inverter 41 that drives the motor MG1 is gated. The cutoff command and the torque command Tm2 * of the motor MG2 are transmitted to the motor ECU 40 (step S250), and this routine is finished. Thus, when the vehicle is in a power running state and the counter electromotive voltage Vmg1 of the motor MG1 is equal to or higher than the voltage VH of the high voltage system power line 54a, the target voltage VH * is set to the required voltage VH2 when the determination power dloss is less than 0. In other words, the gate of the inverter 41 is cut off to suppress the power consumption without executing the field weakening control for the motor MG1.

  According to the hybrid vehicle 20 of the embodiment described above, the back electromotive voltage Vmg1 of the motor MG1 is the voltage VH of the high voltage system power line 54a while the vehicle is in the power running state during the electric running in the motor operation mode. When it is above, the increased power dropV as the power consumption increased by boosting the voltage VH of the high voltage system power line 54a to the required voltage VH2, and the reduced power dlossG as the power consumption decreased by shutting off the gate of the inverter 41. When the determination power loss is less than 0, the target voltage VH * is changed to the necessary voltage VH2 and the inverter 41 of the motor MG1 is gated off, so that the determination power loss is a value. If it is greater than or equal to 0, the target voltage VH * is not changed and the motor MG1 is weakened. By executing the magnetic control, even when the vehicle while being electric traveling in the powering state, the inverter 41 of the motor MG1 and the gate blocking can be improved energy efficiency of the vehicle. Of course, the battery 50 can be charged when the vehicle is in the regenerative state and the back electromotive voltage Vmg1 of the motor MG1 is equal to or higher than the voltage VH of the high voltage system power line 54a during the electric running in the motor operation mode. Sometimes, the inverter 41 of the motor MG1 is gated off, and when the battery 50 is not rechargeable, field weakening control is executed on the motor MG1, so that the energy of the vehicle when the vehicle is in a regenerative state during electric travel Efficiency can be improved.

  In the embodiment, the diodes D1 to D6 of the inverter 41 function as a full-wave rectifier circuit. However, the present invention is not particularly limited thereto, and may function as a half-wave rectifier circuit, for example. Even in this case, even if the counter electromotive voltage Vmg1 generated in the motor MG1 is equal to or higher than the voltage VH of the high voltage system power line 54a, the power consumption can be suppressed by not executing the field weakening control in the motor MG1. The energy efficiency of the vehicle can be further increased.

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problems will be described. In the embodiment, the engine 22 corresponds to the “engine”, the motor MG1 corresponds to the “generator”, the planetary gear 30 corresponds to the “planetary gear mechanism”, the motor MG2 corresponds to the “electric motor”, and the inverter 41 3 corresponds to the “generator inverter”, the inverter 42 corresponds to the “motor inverter”, the battery 50 corresponds to the “battery”, the boost converter 55 corresponds to the “boost converter”, and the motor travel control of FIG. The hybrid electronic control unit 70 that controls the boost converter 55 and the torque commands Tm1 * and Tm2 * of the motors MG1 and MG2 are received while executing the routine and the voltage VH of the high voltage system power line 54a becomes the target voltage VH *. The motor ECU 40 that drives the motors MG1 and MG2 and the engine ECU 24 that controls the engine 22 are It corresponds to a unit. "

  The correspondence between the main elements of the embodiment and the main elements of the invention described in the column of means for solving the problem is the same as that of the embodiment described in the column of means for solving the problem. Therefore, the elements of the invention described in the column of means for solving the problems are not limited. That is, the interpretation of the invention described in the column of means for solving the problems should be made based on the description of the column, and the examples are those of the invention described in the column of means for solving the problems. It is only a specific example.

  As mentioned above, although the form for implementing this invention was demonstrated using the Example, this invention is not limited at all to such an Example, In the range which does not deviate from the summary of this invention, it is with various forms. Of course, it can be implemented.

  The present invention can be used in the manufacturing industry of hybrid vehicles.

  20 hybrid vehicle, 22 engine, 24 engine electronic control unit (engine ECU), 26 crankshaft, 30 planetary gear, 32 drive shaft, 37 differential gear, 38a, 38b drive wheel, 40 motor electronic control unit (motor ECU), 41, 42 Inverter, 43, 44 Rotation position detection sensor, 50 Battery, 54a High voltage system power line, 54b Battery voltage system power line, 55 Boost converter, 57, 58 Capacitor, 70 Hybrid electronic control unit (HVECU), 80 Ignition switch, 81 shift lever, 82 shift position sensor, 83 accelerator pedal, 84 accelerator pedal position sensor, 85 brake pedal, 86 brake pedal position sensor, 8 the vehicle speed sensor, 89 EV switch, D11~D16, D21~D26, D31, D32 diodes, L reactor, MG1, MG2 motor, T11~T16, T21~T26, T31, T32 transistor.

Claims (1)

An engine, a generator, a drive shaft connected to an axle, a planetary gear mechanism in which three rotating elements are connected to three axes of an output shaft of the engine and a rotating shaft of the generator, and connected to the drive shaft A motor, an inverter for a generator for driving the generator, an inverter for a motor for driving the motor, a battery, a battery voltage system to which the battery is connected, the inverter for the generator, and the Connected to a drive voltage system to which an inverter for an electric motor is connected, adjusts the voltage of the drive voltage system to be higher than the voltage of the battery voltage system, and exchanges power between the battery voltage system and the drive voltage system. A boost converter to perform, an operation point of the engine, a torque command of the motor, and a torque command of the generator so as to travel with charging and discharging of the battery In the hybrid vehicle by setting the voltage of the serial driving voltage system and a control means for controlling said boost converter and the generator and the engine and the electric motor,
The control means includes
When the counter electromotive voltage of the generator is higher than the voltage of the drive voltage system while traveling only with power from the electric motor,
When the vehicle is in a regenerative state and the battery is in a chargeable state, the generator inverter is controlled to gate the generator inverter;
When the vehicle is in a regenerative state but the battery is not in a rechargeable state, the generator inverter is controlled to be subjected to field-weakening processing,
When the vehicle is in a power running state, the increased power as the power consumption increased by boosting the voltage of the drive voltage system to a voltage that can be gated off, and the consumption reduced by gate shutting off the generator inverter The determination power is calculated as the sum of the reduced power as the power, and the boost converter is controlled so that the voltage of the drive voltage system can be cut off when the determination power is less than 0. And the generator inverter is controlled so that the generator inverter is gate-cut, and the generator inverter is subjected to field-weakening processing when the power for determination becomes 0 or more. Control,
Means,
A hybrid vehicle characterized by that.

Images